Method and apparatus for tooth whitening

ABSTRACT

Preconditioning mouth rinse, which pre-treats the teeth to better receive a whitening formula containing a photosensitive compound, and a hand-held consumer light source for tooth whitening, which provides rapid tooth whitening, are disclosed. The light source may use a specific range of visible light and also emit heat sufficient to raise the temperature of the teeth a desired amount at a depth up to about 2 mm in the range of about from 1-5° Celsius over a predetermined period of time. The specified wavelengths of the hand-held consumer operable light will activate the photosensitive substance in the whitening formula. The oxidizing compounds may be transparent to light enabling light energy to activate the oxidizing compounds directly on the tooth surface, or to activate a photosensitizing or photosensitive compound added to produce the desired temperature increase.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of Application No. PCT/US2004/010953to Philp, Jr. et al., filed 20 Apr. 2004, which claims the priority ofApplication No. PCT/US2003/017631 to Brown, Jr. et al., filed 5 Jun.2003, and this application claims the priority of U.S. patentapplication No. 60/524,861 to Philp, Jr. et al., filed 26 Nov. 2003, andeach of which is incorporated herein by reference.

This application relates to applicant's concurrently filed ApplicationNo. [applicant's ref. 7273-US], entitled “Method for Whitening Teeth”,filed Dec. 5, 2005, and which is incorporated herein by reference.

FIELD OF INVENTION

The invention relates to a method and apparatus for achieving rapidtooth whitening, which is usable by a consumer. In particular, theinvention relates to a preconditioning mouth rinse, which prepares teethto receive the whitening formula, a whitening compound, which isdirectly applied onto teeth and which contains a photoactive substance,which responds to a safe wavelength of visible light. Also included inthe invention is a hand held consumer light, which emits a biologicallysafe wavelength of light to assist in the whitening of teeth, such as byactivating the tooth-whitening photoactive substance.

BACKGROUND OF THE INVENTION

Teeth become discolored with age, blood, amalgam restorations,antibiotics such as tetracycline, and substances in food, beverages,tobacco and salivary fluid. Tooth structures which are responsible for astained appearance are enamel, dentin, and the acquired pellicle.

Tooth enamel is predominately formed from an inorganic substance,hydroxyapatite crystals, along with approximately 5% organic materials,predominantly collagen. The dentin is composed of about 20% proteinincluding collagen; the balance of inorganic materials includinghydroxyapatite crystals. The acquired pellicle is a proteinaceous layeron the surface of tooth enamel, and that may be removed after anintensive tooth cleaning.

Tooth stains are generally classified as either extrinsic or intrinsic,depending on whether the stain is on the surface of the tooth within theacquired pellicle or within the tooth structure itself within the enamelor dentin. For example, extrinsic staining of the acquired pellicle canoccur from foods or compounds, which contain tannins and otherpolyphenolic compounds which become trapped in the lightly boundproteinaceous layer on the surfaces of the teeth.

Intrinsic staining, on the other hand, occurs when chromogens andpre-chromogens penetrate the enamel and dentin and become tightly boundto the tooth structure. Intrinsic staining can occur when blood oramalgam products leach into the enamel and dentin. Intrinsic staininglikewise can occur systemically from excess fluoride intake duringenamel development leading to a mottled yellow or brown stain offluoresce staining. Intrinsic staining is not removable by mechanicalmethods of tooth cleaning and generally requires the use of chemicals,for example strong oxidizing agents such as hydrogen peroxide which canpenetrate into the tooth structure to effect a change in the lightabsorbtivity of the stain chromogen and/or the solubility of thechromogens.

The desire for whiter, lighter teeth is considered to be cosmetic anddesirable in today's cosmetically-orientated society. Tooth bleaching isgenerally accomplished by gels, pastes, or liquids which contain anoxidizing agent such as hydrogen peroxide that attack (i.e., chemicallyreact with) the chromogen molecules, making them colorless and/or watersoluble, making the tooth appear lighter and brighter, thus resulting inlighter brighter teeth.

The most commonly used oxidizing agent is hydrogen peroxide (H₂O₂), suchas from carbamide peroxide, which is mixed with an anhydrous viscouscarrier containing glycerin and/or propylene glycol and/or polyethyleneglycol. When in contact with water, carbamide peroxide dissociates intourea and hydrogen peroxide. The hydrogen peroxide in the presence ofwater then disassociates into water and a nascent oxygen anion species.It is these highly-nascent oxygen species, which react with the stainmaking them more water soluble, transparent, or both.

There are several known delivery systems to deliver carbamide peroxideto the surfaces of the teeth.

A common approach is to have a dental professional construct acustom-made tray from an impression of the patient's teeth. Theoxidizing gel is dispensed into the tray by the patient and the tray isworn over the teeth intermittently for a period of two weeks to severalmonths, depending on the severity of the staining. This approach cancause tooth sensitivity in over 50% of the patients, and it can beuncomfortable for the patients to wear the tooth bleaching trays. Toothsensitivity is believed to result from the movement of fluid through thedentinal tubules, which is sensed by nerve endings within the tooth. Thecarriers, glycerin propylene glycol and polyethylene glycol, draw fluidstoward them and therefore contribute to the tooth sensitivity oftenexperienced by wearing a bleaching tray.

Another approach is to incorporate the oxidizing agent in a strip andhave the patient wear the strip intermittently over a period of twoweeks. This approach also has the disadvantage of being awkward forpatients to wear, and many patients wearing the strips, also experiencetooth sensitivity. Further, the strips have an inherent problem ofcontacting the teeth only on the facial surfaces and most of thestaining occurs in between the teeth in the interproximal areas where incan be difficult to place the strip, having it in contact with thetooth.

Another recent approach is to simply paint on the oxidizing agent,carbamide peroxide or hydrogen peroxide, directly on the teeth. Inproducts, which are gels containing glycerin and/or propylene glycol orpolyethylene glycol, tooth sensitivity can be experienced, and the gelscan easily be removed by the lips and tongue, thereby decreasing theireffectiveness.

One approach involves dissolving carbamide peroxide in alcohol, and aresin. The resultant compound is applied directly onto the teeth, andthe alcohol evaporates, leaving a sticky resin film or precipitateremaining on the surface, of the teeth. When saliva contacts the teeth,the peroxide is released in a relatively strong concentration for aperiod of up to 20 minutes. This product contains no glycerin, propyleneglycol, or polyethylene glycol and tooth sensitivity is lessened withsome resultant whitening. These products take approximately two weeks ofuse several times a day to achieve a desired result.

To address the problem of taking excessive time to whiten teeth,manufacturers developed systems used by a dentist and only available ina dental office (with and without a light source), to whiten teeth inapproximately one hour. These systems generally use oxidizingcompositions (hydrogen peroxide up to 35%), which are applied directlyon the surfaces of the teeth in a dental office under the supervision ofa dentist or dental hygienist. Owing to the high concentration ofoxidizing agents contained in these in-office products, they can behazardous to the patient if not handled carefully. The patient's softtissues—gingiva, lips and tissues—must be isolated from potentialexposure to a concentration of oxidizing agent by the use of a rubberdam or by covering the soft tissues with a polymerizable resin that isshaped to conform to the gingival contours and subsequently cured by ahigh intensity light source operable only by a dentist. These dentistin-office whitening systems are expensive to the patient.

Known patents directed to these various tooth whitening systems include:

U.S. Pat No. 4,952,143 to Becker et al.; and

U.S. Pat. No. 5,032,178 to Cornell.

These known systems have drawbacks.

A commercial product, called Opalescence, from Attica Dental Products,Inc., South Jordan, Utah is known.

Further known systems are set forth in:

U.S. Pat. No. 5,785,527 to Jensen et al.; and

U.S. Pat. No. 6,517,350 to Diasti et al.

One commercially available illuminating system is from Union Broach, aHealth/Claim Company, New York, N.Y.

Other known United States patent documents include:

U.S. Pat. No. 4,450,139 Bussiere et al.;

U.S. Pat. No. 5,457,611 Verderber;

U.S. Pat. No. 6,331,111 Cao;

U.S. Pat. No. 6,343,933 Montgomery;

U.S. Pat. No. 6,416,319 Cipolla;

U.S. Pub. No. 2003/0017435 Ibsen et al.;

U.S. Pub. No. 2003/0036037 Zavitsanos et al.; and

U.S. Pat. No. 4,661,070 to Friedman.

There is a need for improved compositions and devices for whiteningteeth that are capable of whitening the teeth rapidly and inexpensivelyby consumers without damaging the tooth enamel, dentin, or the pulp, andthat are able to be used at a lower concentration of peroxide, thusenabling the patient to use the product at home without harming thetissues, or causing tissue irritation, or causing tooth sensitivity.

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the invention to provide a tooth whitening method,system, and device that overcome the drawbacks of prior art methods,systems, and devices.

It is a further object of the invention to provide a tooth whiteningsystem, which provides a more even whitening of the teeth than knownsystems.

It is yet another object of the invention to provide a tooth whiteningsystem, which is self-regulating and avoids overheating of the user'steeth being whitened, for example.

Another object of the invention is to provide a tooth whitening system,which may be performed without the use of a dental dam or withoutprotecting the oral tissues by covering them with a polymerizable resin.

It is an object of this invention to provide a tooth whitening system,the action of which is accelerated by light-and-heat energy, which theconsumer can use at home, thereby being more cost-effective thanin-office teeth whitening regimes.

It is a further object of this invention to provide a tooth whiteningsystem, which shortens the treatment time to obtain a given level ofwhitening using at-home paint-on whitening products or bleaching trayregimes.

Another object of this invention is to use a solution or gel whichtemporarily adheres to the teeth, and which can be directly applied tothe teeth by consumers at their home or elsewhere.

It is yet another object of this invention to use a solution or gel witha concentration of peroxide which will reduce or eliminate irritation ofthe patient's tissues making it better and more comfortable for thepatient.

A further object of the invention is to provide a preconditioning mouthrinse formulated to prepare teeth for a tooth whitening agent.

It is yet another object of this invention to use a hand-held lightsource which uses batteries or a rechargeable power source, and that canprovide an even illumination of visible- and light-heat in the range of1° to 5° C. against the surfaces of the front anterior teeth.

It is a further object of this invention that the light/heat source oflight be controlled so as not to exceed a 5° C. increase in temperatureno matter how long the consumer applies the light/heat source to thesurfaces of the anterior teeth.

It is a further object of this invention to use a liquid solution or gelwhich is relatively transparent and allows the transmission of heat intothe enamel or dentin to achieve a temperature increase of about 1° to 5°C. for approximately 1-2 minutes to effect a biologically-compatible andeffective level of tooth whitening.

Another object is to provide a tooth whitening device including ahand-held light source used by the consumer that produces a slightincrease in temperature of from 1°-5° C. either on the surface of thetooth directly or within the tooth structure at a depth of 1-2 mm fromthe surface with the use of photosensitive compounds for producing theslight increase in temperature.

A further object is to provide a tooth whitening device with anattachment which is curved to simulate the natural curvature of the archof the teeth, and which is provided in several sizes; e.g., small,medium, and large.

A further object is to provide a tooth whitening device with a timerwhich automatically turns the light source off at the desired time alongwith a device for indicating the light source is on.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a left side view of an embodiment of a hand-held consumerlight for use with a tooth whitening system according to the invention;

FIG. 2 shows a front view of the hand-held consumer light of FIG. 1 foruse with the tooth whitening system according to the invention;

FIG. 3 shows a bottom view of the hand-held consumer light of FIG. 1 foruse with the tooth whitening system according to the invention;

FIG. 4 shows a top view of the hand-held consumer light of FIG. 1 foruse with the tooth whitening system according to the invention;

FIG. 5 shows a right, partially broken away side view of the hand-heldconsumer light of FIG. 1 in use; and

FIG. 6 shows a perspective view of the hand-held consumer light for usewith the tooth whitening system according to the invention in anoptional recharger base.

DETAILED DESCRIPTION OF THE INVENTION

These embodiments are set forth to describe and illustrate theinvention, but are not intended to be limiting. The invention mayachieve rapid tooth whitening by using a preconditioning rinse and handheld consumer light for emitting optical energy and a safe amount ofheat to penetrate an oxidizing compound placed directly on the toothsurface to be whitened.

There are known compositions that include light (or heat), which can beadded to an oxidizing compound (e.g. gel or solution) and disperseddirectly in and homogenously throughout the oxidizing compound. Somereferences and text are noted: for example Kirk-Othmer Encyclopedia ofChemical Technology, 4th edition, volumes 4 (1992), 13 (1995), 18(1996), John Wiley & Sons, N.Y.; Goldstein and Garber, Complete DentalBleaching, Quintessence Publishing Co. 1995; and the Journal of theAmerican Dental Association, Vol. 128, Special Supplement, April 1997.

For tooth whitening the greatest oxidizing activity is required in thefirst few millimeters of enamel and in the dentin at the tooth surface.

The present invention is more effective at removing teeth stains atlower levels of active oxidizing agents and lower levels of heat thanknown devices, thereby resulting in a better whitening system which canbe used safely by a consumer and which can result in more rapid toothwhitening. To better understand the tooth whitening process in thepresent invention some background information is desirable.

The oxidizing agent, in the present invention, may be carbamide peroxide(urea hydrogen peroxide). This agent is broken down in the presence ofwater to urea and hydrogen peroxide (H₂O₂). The hydrogen peroxide isunstable and in the presence of light or moisture it decomposes intowater H₂O and an Oxygen free radical (i.e., O⁻ or nascent oxygen speciesor oxygen free radicals). It is these oxygen free radicals, which attackthe stain molecules and make them water-soluble, transparent, or both,resulting in the lighter brighter teeth.

The oxygen free radicals which are formed are highly reactive and willreact with each other to produce O₂ (Oxygen) rapidly. It is the abilityand quantity of the free radical oxygen anions to reach the stainmolecules and react with them, which determines the efficacy of thewhitening process. The speed of the whitening process can besignificantly enhanced with the addition of a slight amount of heat inthat solution (dissolving) occurs more rapidly in a warmer environmentthan a cooler one, for example.

Detailed Description of the Mouth Rinse

The invention achieves rapid tooth whitening by using a preconditioningmouth rinse, which prepares the tooth surface to receive the whiteningcompound alone with a photosensitive compound in the whitening compoundfollowed by using optical energy which penetrates through the existingformulation, which is placed on the tooth surface to be whitened.

To enhance tooth whitening at the surface of and within the first fewmillimeters of enamel below the surface, the present invention includesa preconditioner, such as a preconditioning mouth rinse, which preparesthe teeth to receive the whitening compound. The mouth rinse isformulated to kill bacteria which produce peroxidase enzymes, create anenvironment on the tooth surface which has a slightly basic pH, andcontains a surfactant thereby improving wetting of the tooth surface bythe whitening compound and allowing deeper penetration. The surfactantwill also help the oxygen free radicals react with the tooth stain(chromogen molecules) and within the tooth surface; the mouth rinse mayalso contain substances which destroy and prevent oral malodors andflavoring compounds.

The mouth contains peroxide enzymes including salivary peroxidase,catalases and bacteria, which produce peroxidases, which are enzymeswhich destroy peroxide. It would be desirable to have in thepreconditioning or activator mouth rinse a disinfectant which would killthe bacteria which produce peroxidases thereby increasing the quantityof hydrogen peroxide, which produces the oxygen free radicals.

Common disinfectants in known mouthwash preparations may be used.

If the pH in the environment of the oxidizing compound, hydrogenperoxide, for example, is increased, the oxidizing compound will degradeand generate free radicals more readily. Furthermore, most peroxidaseenzymes (including salivary peroxides and catalases) have low activitiesabove a pH of 8.

It is therefore desirable to have an alkaline pH in the activator rinseto pre-treat the environment agent to have a pH of about 8. Sodiumbicarbonate, which is safe and commonly used in dental toothpastes andrinses, has a pH of 8.2. The ideal pH to break down hydrogen peroxide isbetween a pH range of 7.9-9.0, a higher pH can become caustic to theoral tissues.

pH Adjusting Chemicals

Sodium carbonate, potassium carbonate, sodium hydroxide, ammoniumhydroxide, potassium hydroxide, sodium phosphate di- and tri-basic,potassium phosphate di- and tri-basic, sodium tripolyphosphate,tris(hydroxymethyl)aminomethane, polyethylenaimine, triethanolamine, andother alkaline agents. Acidic pH adjusting agents, such as citric acid,phosphoric acid, and others may also be used alone or in conjunctionwith an alkaline pH adjusting agent to obtain the desired pH and toprovide buffering capacity.

The performance enhancing adjuvant may include at least one of a buffer,a surfactant, a thickener, a film forming ingredient, a penetrationenhancer, and desensitizing agent.

Surfactants (Surface Active Agents)

Surfactants may be used to lower the surface tension of thecompositions. Lowering of the surface tension allows for better wettingand spreading of the composition on the tooth surface. Some surfactants,such as zwitterionic and fluorinated surfactants, have been seen toincrease the penetration of the present inventive compositions into thetooth structure.

Useful surfactants may include those identified in U.S. Pat. No.5,279,816 to Church et al. and U.S. Pat. No. 5,302,375 to Viscio, eachof which is incorporated herein by reference in its entirety.

Zwitterionic surfactants have positive and negative charges thatsignificantly improve penetration of peroxide into the tooth. It is tobe understood that additional useful surfactants will become apparent tothose skilled in the art based upon the disclosure herein. The level ofsurfactant, when present, may be from about 0.001% to about 10.0% byweight of the accelerator composition, and may be from about 0.1% toabout 1% by weight of the accelerator composition.

Thickeners

A thickener may also be added to the accelerator composition as aperformance enhancing adjuvant to increase the contact time of theaccelerator on the tooth surface.

In one embodiment, the thickener provides coating properties for theaccelerator by forming a film when applied to the teeth.

Thickeners such as neutralized carboxypolymethylene and otherpolyacrylic acid polymers and copolymers, hydroxypropylcellulose andother cellulose ethers, salts of poly(methyl vinyl ether-co-maleicanhydride), polyvinyl pyrrolidone (PVP), poly(vinylpyrrolidone-co-vinylacetate), silicon dioxide, fumed silica, stearic acid esters, and othersare found to have utility in the formulation of the oxidizingcompositions and tooth whitening accelerator compositions.

Polymers utilized as thickeners may also serve as film-forming agentsthat provide for even distribution of the accelerator composition overthe tooth surface. It is to be understood that additional usefulthickeners will become apparent to those skilled in the art based uponthe disclosure herein.

The level of thickener, when present, is highly dependent upon the typechosen, but in general may be included in the composition at aconcentration of from about 0.1% to about 20.0% by weight of thecomposition, and may be at a concentration of from about 0.1% to about5% by weight of the accelerator composition.

Flavorants

Flavorants may also be included in the accelerator composition in orderto improve palatability and acceptance by the user or the patient.Flavorants are generally known in the art and include, among others,spearmint, peppermint, anethole, menthol, stevia, citrus flavors, andvanilla.

It may be desirable to provide within the composition an artificialsweetener selected from the group including sodium saccharin andpotassium acesulfame. Sugars and sugar alcohols, such as sucrose,fructose, glucose, xylitol, maltitol, mannitol, sorbitol, and othermono-, di-, tri-, and higher monosaccharides may be used as sweeteners.For example, glycine may also serve as a sweetener and has the abilityto mellow saltiness and bitterness of the pH adjusting agent.

Both flavorants and sweeteners, when present, may each be included at alevel of from about 0.01% to about 5.0% by weight of the composition.

Other artificial sweeteners are contemplated to have utility in thepractice of the present invention, limited only by their solubility andstability in the compositions.

EXAMPLE OF FORMULA FOR MOUTH RINSE

Supplier and miscellaneous Ingredient Concentration information NP-9,ethoxylated 0.65 mls Brenntag, Univar nonyphenol, 9 molar EO. PeppermintOil 1.4 mls Lebermuth Nutrasweet ® 0.75 grams The Nutrasweet CompanyGranular 100 Glycerin 99.5% 30 mls Brenntag, Univar Kosher food gradeSodium Bicarbonate 2 grams Brenntag, Univar food grade Sodium Carbonate0.1 grams Brenntag, Univar food grade Benzethonium 0.15 grams Lonza IncChloride Purified Water Balance to 1 Distilled or deionized gallon(i.e., 3.785 liter) or reverse osmosis grade Ethanol 75% or ˜10 mls FoodGrade greater

Detailed Description of the Directly Applied Tooth Whitening Formula

Along with a safe concentration of an oxidizing agent of approximately8-12% carbamide peroxide by weight the oxidizing solution or gel can beincorporated with light-activated photosensitizing agents, which caninclude any compounds capable of absorbing light energy at biologicallyacceptable wavelengths for use in the oral cavity.

Examples of compounds which may convert light energy to heat or chemicalenergy include readily available compounds, such as semiconductorparticles, e.g., titanium oxide and/or zinc oxide. If photosensitizersare used, such may be allowed to penetrate into the enamel or dentinprior to the application of the light, depending on the intended use andthe chemical composition of the whitener used. Therefore the particlesize should enable penetration of the photoactive substance.

EXAMPLE OF TOOTH WHITENING FORMULA

% by COMPOUND Weight RANGE % Ethyl Alcohol 73.75 Hydrogenated Ester of13.87 0.001-35.00 Rosin Urea (Carbamide) 11.10 0.001-25.00 HydrogenPeroxide Hydroxypropylcellulose 0.55 0.001-10.00 1500 cps Flavoring-Menthol 0.22 0.001-15.00 Flavoring- Peppermint 0.20 0.001-15.00 Oil ZincOxide (micro 0.15 0.001-5.00 particles) Flavoring- Aspartame 0.150.001-5.00

A supplier of the zinc oxide (micro particles) is B.F. Goodrich.

EXAMPLE OF ALTERNATIVE FORMULA

COMPOUND %/w RANGE Anhydrous Propylene Glycol 54.3%   0.001-75.00 FumedSilica 20% 0.001-40.00 Sodium Perborate Monohydrate 25% 0.001-40.00Sodium Saccharine 0.7%  0.001-5.00 

Viscous whitening agent which may be painted on the teeth may be asfollows.

The viscosity of one or more of whitening agents may be varied dependingon the intended use, as described in detail below.

The whitening agent may be a “paint-on” whitening agent which can beapplied to the teeth, adheres to the teeth, and requires no protectivetape, film, or cover when on the teeth to avoid being wiped off by theuser's gums or saliva. Please see Applicant's co-pending application no.PCT/US03/17631, filed 5 Jun. 2003, and which is incorporated herein byreference.

It is contemplated that in any of the embodiments of any suitableviscous, solid or semi-solid whitening agent may be used that can whitenwithout irritating the mouth tissues.

In an embodiment of the invention, the whitening agent may have thefollowing range of compositions.

Whitening Agent Composition A2 (To Yield 100 ml of Composition)

Ethanol (ethyl alcohol) balance ml Urea Peroxide .001-40 g Resin .001-30g Hydroxyl propyl cellulose .001-20 g total 100 ml

A further embodiment of the whitening agent follows.

Whitening Agent Composition A4 (Total Yield 100 ml of Composition)

Ethanol (ethyl alcohol) balance ml Urea Peroxide 8 g Resin 10 g Hydroxylpropyl cellulose .5 g total 100 ml

Whitening agent of composition A3 may be made with 100% pure undenaturedethyl alcohol and 98% pure urea peroxide.

Rosin may be substituted for resin in all formulas.

Urea hydrogen peroxide may be substituted for urea peroxide in allformulas.

Whitening agents may be formulated as follows:

Whitening Agent Composition A5 (Total Yield 100 ml of Composition)

Rosin .001-30 g Urea hydrogen peroxide .001-40 g Hydroxypropyl cellulose1500 cps .001-20 g Ethyl alcohol (95%) balance ml Total Volume 100 ml

The following is an example of a tooth whitening compound that has beenformulated in accordance with the invention.

The following is the formulation of a procedure for making 100 ml of aSolution No. 16.

In the following formula, the resin, the urea hydrogen peroxide USP, andthe hydroxypropyl cellulose 1500 cps are all expressed as a weight pervolume (w/v; i.e., g/100 ml) and the ethanol 95 was added in a quantityas needed (q.s.) to yield the desired 100 ml of whitening agent.

Whitening Agent Composition of Solution No. 16 (Total Yield 100 ml ofComposition)

Rosin 12.5 g Urea hydrogen peroxide 8.0 g Hydroxypropyl cellulose 1500cps 0.5 g Ethyl alcohol (95%) balance ml Total Volume 100 ml

Solution No. 16 was formulated as follows to yield 100 ml of product:

-   -   1. Dissolve 12.5 g of resin in 75 ml of the ethanol in a beaker        having a spin bar therein;    -   2. The spin bar was spun using the spinning device (stirrer) of        an unheated hot plate of the type having a magnetic stirrer        disposed therein, the spinning was continued until the unheated        rosin and ethanol solution was clear;    -   3. 8 g of the urea hydrogen peroxide were weighed out and ground        into a fine powder using a mortar and pestle, added to the rosin        and ethanol solution, and then stirred on the spinning device. A        cloudy solution resulted.    -   4. As the rosin and ethanol solution was spinning, the 0.5 g of        hydroxypropyl cellulose was added gradually (sprinkled into the        vortex of the spinning solution resulting from the magnetic stir        bar) in small amounts at a time. The spinning was continued for        about an hour until the solution began to gel. Enough ethyl        alcohol (95%) was added q.s. to bring the volume up to 100 ml,        and the spinning was continued.    -   5. The mixed solution was put in a refrigerator (at about 40°        F.) and left overnight (i.e., about 19-20 hours) to allow the        solution to completely hydrolyze.    -   6. The refrigerated solution was removed from the refrigerator        and again spun at room temperature at about 70° F.) for about 30        minutes to throughly mix the solution.    -   The prepared solution was then put into the desired containers.

It should be noted that in Step 4 of spinning the solution having therosin, the urea hydrogen peroxide 1500 cps, and the hydroxypropylcellulose, the added materials may not throughly dissolve. It appearsthat the step of allowing the solution to sit overnight in therefrigerator for a period of time, and then remixing the solutionsucceeds in yielding a homogeneous solution with the added materialsdissolved and dispersed throughout.

The following is the formulation of a Solution No. 18 that has beenmade.

Whitening Agent Composition Of Solution No. 18 (Total Yield 60 ml (i.e.,51.43 g) of Composition)

Rosin 7.5 g Urea hydrogen peroxide 3.6 g Hydroxypropyl cellulose 1500cps 0.3 g Ethyl alcohol (95%) 40.0 g  Spearmint Extract (1 drop) 0.03 g Total Weight 51.43 g 

Thus, Solution No. 18 can be expressed on a weight per weight (w/w)basis of about 14.6% rosin; 7.0% urea hydrogen peroxide; 0.6%hydroxypropyl cellulose 1500 cps; 77.8% ethyl alcohol; and 0.06%spearmint extract; the total is not exactly 100% owing to the roundingof the percentages to one(1) significant digit.

Solution No. 18 was prepared in a manner analogous to that as describedabove in connection with the preparation of Solution No. 16.

Detailed Description of the Hand Held Consumer Light

The present invention provides a light source for tooth whitening whichuses a battery or a rechargeable power supply and, which may be held bythe consumer (i.e., the patient) outside the patient's mouth in a mannerto provide a uniform illumination of the patient's anterior teeth toproduce a uniform increase in temperature of the anterior surfaces ofthe anterior teeth from about 1° C. to a maximum of 5° C. over a periodof application of a maximum of 10 minutes. Also the light emits abiologically safe wavelength of visible light between 350-700nanometers, which can penetrate the tooth and react with thephotoactivator substance speeding the release of the oxidizing compound.

As described in the literature, an unexpected benefit of utilizing atransparent solution or gel containing the oxidizing compound is thatcertain visible wavelengths of light seem to be absorbed by toothchromogens (stains) in a manner that promotes their oxidation to anon-chromogenic state. Reflectance studies demonstrate that enamel anddentin transmit green light, reflect yellow and red light, and absorbblue light. Light can be absorbed by the molecules responsible for toothdiscoloration, thus the chromogens may, in effect, act asphotosensitizers. In theory, light of a visible wavelength may utilize atooth chromogen molecule as a photosensitizer in order to improve theefficiency of the oxidizing agent to remove the chromogen (stain). Yet,prior to the present invention no one had previously reduced lightintensity levels—to levels which could be used by a consumer witheffective tooth whitening results.

The device illustrated in FIGS. 1-6 is a consumer hand-held light sourceaccording to the invention that is capable of generating a desiredamount of heat of approximately 1°-5° C. within 2 mm of the toothsurface. This may be considered a desired temperature increase. Thedesired temperature increase may be administered up to about 10 minutes.An example of a known light source that meets these requirements is aXenon light. Other light sources may be Quartz or Halogen light sourcesor other sources not limited to the ones described, as will be readilyapparent to a person having ordinary skill in the art.

The power source shown in the FIGS. 1-6 is battery power forconvenience; however, direct current may also be considered enabling thedevice to be free-standing. FIG. 6 shows the power source may include arechargeable battery.

Attachment(s) which may be used with above-described inventive hand-heldconsumer light containing the illuminating bulb(s) will be shaped tofollow the natural curvature of the upper arch enabling an evendisbursement of light and heat to all the anterior teeth to provide evenwhitening results. Attachments may be provided in various sizes tofacilitate different size arches—large, medium and small.

Another attribute of the attachment is that it may be enclosed,completely or partially, by an encompassing soft material which will actas a cheek and lip retractor keeping the light source a given requireddistance from the tooth surface to produce the temperature rangerequired and to isolate the teeth while the light is activated. Thelight sources capable of causing a desired increase in temperature areconsidered to be included in this invention. The desired temperatureincrease may be as described above. Infrared light more readilypenetrates the tooth structure and may cause an excessive temperaturerise in the pulp. Suitable bulbs which can produce heat are linear flashlamps, tungsten, halogen, metal halides, xenon short arc and, mercuryshort arc, as well as others which achieve the desired results.

FIGS. 1-6 illustrate an embodiment of a hand-held light source 10 foruse with a tooth whitening system according to the invention.

Light source 10 may include a handle 20 and an upper part or head 30. Ablue lens 32 may be provided. Blue lens 32 filters out certainwavelengths of light, which wavelengths may be undesirable wavelengthsof light, depending on the methodology consistent with the invention.Lens 32 allows the desired wavelengths of light to pass through. Lens 32may be provided on head 30 and be configured in the desired shape toassist in causing light rays to be directed at and strike the whiteningcompound applied to a user's teeth 33 in the desired amount andintensity for causing the predetermined chemical reaction effecting thewhitening of the teeth, along the lines described above.

In order to provide the desired light and/or heat source, one or morelight sources or elements or bulbs may be provided, such as theillustrated light bulbs 44 and 46.

Light rays 48 of the desired wavelength and intensity are schematicallyshown in FIG. 5.

A power source 50, such as a battery, alternating or direct current, asdesired, may likewise be provided. Also, rechargeable batteries may beutilized.

It will be appreciated that the configuration and the location of lightsources 44 and 46, as shown in the illustrated array, will effect thedesired consistent, uniform chemical reaction of the tooth whiteningagent provided on the user's teeth, in use.

Light source 10 may further be provided with an on-off switch 54 forcontrolling the administering of light from the light source. A timermay be provided for controlling the length of time the light source maybe used within a given period of time, regardless of the number of timesthe user actuates switch 54. Alternatively, light bulbs 44 and 46 may beactivated (i.e. ON) only when switch 54 is actuated.

One or more attachments 56 may be provided to accommodate differentsizes, widths, and arch sizes of the user's mouth. Attachment 56 may beprovided with one or more extensions 58 and 60, as well as with apredetermined curvature 62, dependent on the size requirements of theuser's mouth, as outlined above. In addition, a height 64 and a width66, as well as other configuration considerations will be taken intoaccount, dependent on the user's mouth contour, and the type of lightsource 44 and 46 provided, for example.

In use, thanks to the configuration of attachment 56 and its associatedconfigured extensions, size, and shapes, attachment 56 will contact thelips and mouth tissue in a region 70, as shown in FIG. 5. This contactregion 70 establishes a predetermined distance 72 between attachment 56and teeth 33. Thus, a desired offset or spacing 74 between lens 32 andlight sources 44 and 46 and teeth 33 is established. In that manner, theintensity of light rays 48 is governed and predetermined so that thepredetermined degree of temperature increase within the outer 2 mm ofthe tooth surface is established, as described above.

Still further, thanks to the establishment of a predetermined angle 76between head 30 and body 20 of light source 10, the user is able tocomfortably and accurately direct light rays 48 at teeth 33 in thedesired manner. Thus, the goal of home use by a person whose teeth 33are to be whitened is achieved.

FIG. 6 illustrates a recharger 80 which may be provided for rechargingrechargeable battery 50.

Recharger 80 may be provided with an electrical cord and a plug 84, aswill be readily understood by a person having ordinary skill in the art.In the case where the recharger is powered by alternating current, suchas typical AC household electrical outlets, an AC to DCconvert/transformer or a microchip to convert AC effectively into DC maybe provided in the recharger base 86, as will be readily understood.Base 86 may be configured for being freestanding and sized and weightedso that light source 10 may be placed on a countertop for recharging, asshown.

In use, it will have been appreciated that the user may bare his or herteeth 33, such as by smiling, and face lens 32 at the same level andorientation as lens 32 of FIG. 5, with light source 10 disposedsubstantially adjacent the teeth, as shown, and as described above.

There may be a fiber optic strand or cable or device to guide and directlight from the light source to a desired location.

The location may be selected so as to illuminate and whiten one or moreof the user's teeth.

While this invention has been described as having a preferred design, itis understood that it is capable of further modifications, and usesand/or adaptations of the invention and following in general theprinciple of the invention and including such departures from thepresent disclosure as come within the known or customary practice in theart to which the invention pertains, and as may be applied to thecentral features hereinbefore set forth, and fall within the scope ofthe invention or limits of the claims appended hereto.

1. A tooth whitening system, comprising: a) a portable, self-contained,hand-held light source; b) the hand-held light source including: i) ahousing; ii) the housing including a handle configured for beingmanipulated by a user; iii) a head; iv) a lens provided on the head ofthe housing at a distance from the handle; v) a self-contained lightelement provided in the housing and located for emitting light throughthe lens, the light element, in use, emitting light of a wavelengthsuitable for activating a light-activated tooth whitener, in use, when atooth whitener is provided on a user's teeth; and vi) a power sourceprovided in the housing, the power source being electrically connectedwith the light element; and c) the head of the housing being disposedrelative to the handle at a predetermined angle so that, in use, a usermay direct light emitted by the light element at the user's own teeth;2. A tooth whitening system as in claim 1, wherein: a) the handleextends at an angle of about 45°-135° relative to a direction ofextension of the head of the housing.
 3. A tooth whitening system as inclaim 1, wherein: a) the light element includes a halogen light.
 4. Atooth whitening system as in claim 1, wherein: a) the light elementincludes a tungsten light.
 5. A tooth whitening system as in claim 1,wherein: a) the light element includes a xenon light.
 6. A toothwhitening system as in claim 1, wherein: a) a switch is provided, theswitch being electrically connected with the power element for switchingthe light element on and off.
 7. A tooth whitening method, comprising:a) providing a portable, self-contained, hand-held light source thehand-held light source including: i) a housing; ii) the housingincluding a handle configured for being manipulated by a user; iii) aself-contained light element provided in the housing and located foremitting light of a wavelength suitable for activating a light-activatedtooth whitener, in use, when a tooth whitener is provided on a user'steeth; iv) a power source provided in the housing, the power sourcebeing electrically connected with the light element; and v) the lightelement being disposed relative to the handle for emitting light at apredetermined angle so that, in use, a user may direct light emitted bythe light element at the user's own teeth; and b) providing a toothwhitener on a user's teeth.
 8. A tooth whitening method as in claim 7,wherein: a) the light element includes a halogen light.
 9. A toothwhitening method as in claim 7, wherein: a) a mouth rinse is provided,the mouth rinse being selected for preconditioning a user's teeth forreceiving a whitening compound.
 10. A tooth whitening method as in claim7, wherein: a) the tooth whitener includes a light-activated toothwhitener provided on a user's teeth.
 11. A tooth whitening method as inclaim 7, wherein: a) the tooth whitener includes a heat-activated toothwhitener provided on a user's teeth.
 12. A tooth whitening method as inclaim 7, wherein: a) a preconditioning rinse is provided, thepreconditioning rinse being formulated to pretreat the environment ofthe user's teeth to be in a pH range of about 7.9-9.0.
 13. A toothwhitening method as in claim 7, wherein: a) a blue light filter whichfilters out undesirable wavelengths of light is provided, the blue lightfilter thus enabling a blue wavelength to be emitted to penetrate thetooth.
 14. A tooth whitening method as in claim 12, wherein: a) thepreconditioning rinse is formulated to kill bacteria which produceperoxidase enzymes.
 15. A tooth whitening method as in claim 9, wherein:a) the mouth rinse includes a mouth rinse having a formula: IngredientConcentration NP-9, ethoxylated 0.65 mls nonyphenol, 9 molar EO.Peppermint Oil 1.4 mls Nutrasweet ® 0.75 grams Granular 100 Glycerin99.5% 30 mls Kosher food grade Sodium Bicarbonate 2 grams food gradeSodium Carbonate 0.1 grams food grade Benzethonium 0.15 grams ChloridePurified Water Balance to 1 gallon (i.e., 3.785 liter) Ethanol 75% or˜10 mls greater


16. A tooth whitening method as in claim 7, wherein: a) the toothwhitener includes a tooth whitener having a formula: % by COMPOUNDWeight RANGE % Ethyl Alcohol 73.75 Hydrogenated Ester of 13.870.001-35.00 Rosin Urea (Carbamide) 11.10 0.001-25.00 Hydrogen PeroxideHydroxypropylcellulose 0.55 0.001-10.00 1500 cps Flavoring- Menthol 0.220.001-15.00 Flavoring- Peppermint 0.20 0.001-15.00 Oil Zinc Oxide (micro0.15 0.001-5.00  particles) Flavoring- Aspartame 0.15 0.001-5.00 